Related Experiment Video
Updated: Jul 14, 2026

Synthesis and Assay of Vibrio Quorum Sensing Inhibitors
Published on: May 31, 2024
Crystal structure of the Vibrio cholerae quorum-sensing regulatory protein HapR
Rukman S De Silva1, Gabriela Kovacikova, Wei Lin
1Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA.
Abstract:
Quorum sensing in Vibrio cholerae involves signaling between two-component sensor protein kinases and the response regulator LuxO to control the expression of the master regulator HapR. HapR, in turn, plays a central role in regulating a number of important processes, such as virulence gene expression and biofilm formation. We have determined the crystal structure of HapR to 2.2-A resolution. Its structure reveals a dimeric, two-domain molecule with an all-helical structure that is strongly conserved with members of the TetR family of transcriptional regulators. The N-terminal DNA-binding domain contains a helix-turn-helix DNA-binding motif and alteration of certain residues in this domain completely abolishes the ability of HapR to bind to DNA, alleviating repression of both virulence gene expression and biofilm formation. The C-terminal dimerization domain contains a unique solvent accessible tunnel connected to an amphipathic cavity, which by analogy with other TetR regulators, may serve as a binding pocket for an as-yet-unidentified ligand.
Related Concept Videos
Gene Regulation in Microbial Communities: Quorum Sensing
Regulation of Bacterial Virulence
Other Stress Responses in Bacteria
Bacterial Signaling
Cholera
Molecular Chaperones and Protein Folding
The...

